Beyond the Scale: Exploring the Factors Behind Obesity#
Obesity has become a heavyweight issue in public health. Especially in the United States. Finding the exact causes of obesity is tough because many different factors contribute to it. It’s a complicated issue with many conflicting views.
One major factor is diet. Numerous studies show a strong link between poor nutritional habits and obesity. Diets high in processed foods, sugars, and unhealthy fats are common in many parts of the world, particularly in areas with high obesity rates. For instance, a study published in the Journal of Nutrition (https://ijbnpa.biomedcentral.com/articles/10.1186/s12966-020-00963-2) found that individuals who consumed high amounts of fast food and sugary beverages were significantly more likely to be obese compared to those with healthier eating habits.
Conversely, another study published in the International Journal of Obesity highlights the role of genetic factors, indicating that individuals with certain genetic markers are more predisposed to obesity, regardless of their diet and physical activity levels. (https://www.hsph.harvard.edu/obesity-prevention-source/obesity-causes/genes-and-obesity/)
Political factors, such as government policies and public health initiatives, also impact obesity rates. Policies that promote healthy eating and physical activity can help reduce obesity, while those that do not address these issues may add to the problem.
As such, we researched the different correlations behind obesity, focusing on how diet quality, income levels, and voting behaviour influence obesity rates in the United States.
Nutritional Disparities#
It’s widely recognized that obesity is closely linked to poor dietary habits. Consuming unhealthy foods regularly can significantly impact one’s health. Financially, Americans are responsible for nearly half of the global expenditure on fast food, according to a report by Fortune Business Insights (https://www.fortunebusinessinsights.com/fast-food-market-106482). Additionally, during the period from 2013 to 2016, 36.6% of adults in the United States consumed fast food on any given day, as reported by the CDC (https://www.cdc.gov/nchs/products/databriefs/db322.htm). We plotted the obesity rates in the USA over the years, and our analysis compared the average nutritional values of typical meals to those of fast food to highlight the dietary factors contributing to these trends.
%run obesity_time.ipynb
The first graph shows a normalized comparison of nutritional content between fast food and typical meals, illustrating that fast food contains significantly higher levels of calories, fat, cholesterol, sodium, and sugar. These nutritional disparities contribute to adverse health effects, including obesity.
Part of the reason behind the high obesity rates is explained by the nutritional content of fast food. Research indicates that consuming ultra-processed foods leads to higher calorie intake and weight gain compared to minimally processed foods (https://pubmed.ncbi.nlm.nih.gov/31105044/) . Processed foods, like fast food, may be convenient and sometimes more affordable, but they often contain higher levels of sodium, sugar, and unhealthy fats, as shown in the bar graph above. These factors make fast food a significant contributor to the obesity epidemic.
Fast food and Obesity Density#
When we started researching the causes behind obesity, the first thing that came to mind was to plot the number of fast food restaurants against the adult obesity rate. Intuitively, one might expect that a higher density of fast food restaurants would correlate with higher obesity rates, given the association between fast food consumption and poor dietary habits. When you look at the world’s obesity ranking and fast food consumption, you could argue that there seems to be a correlation. (https://worldpopulationreview.com/country-rankings/fast-food-consumption-by-country, https://worldpopulationreview.com/country-rankings/fast-food-consumption-by-country)
However, as illustrated in the scatter plot, there appears to be no significant correlation between the number of fast food restaurants per 100,000 people and the adult obesity rate across U.S. states. The correlation coefficient is -0.16, indicating a very weak negative relationship, so we continued our search for more nuanced correlations.
Salary and Obesity#
Next, we explored the influence of salary on obesity across the United States. Given that individuals with higher incomes often have access to more expensive, healthier food options, as well as better education and healthcare, we were interested in investigating whether there is a correlation, and if so, how strong it is.